The 22-year-old is playing the part of Ed Lee, a mathematics genius who becomes an unlikely ally for Natasha Williams (Valentina Novakovic) in an upcoming storyline.
Ed will appear on screens for four months, and has been tipped to make a big impact on Ramsay Street life as he introduces Tash to "some of his unusual pastimes".
Gregory commented: "He is very different but also likeable - I'm really enjoying playing him."
Neighbours fans previously saw Gregory in Erinsborough briefly a few years ago, when he appeared as a boyfriend for Rachel Kinski (Caitlin Stasey).
Gregory joked: "It was a very short romance - about three episodes!"
Ed's first scenes will air in late June on Channel 5 in the UK.
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